Egyptian marine fisheries contribute to the economy of the country where it provides an important source for food and employment. There are many challenges that affected the sustainability of marine fish stocks from which overfishing due to the increasing fishing effort. In the present study, annual catch and effort data were analyzed to estimate the maximum sustainable yield (MSY) and the corresponding level of fishing effort (f_max) for both the Mediterranean & Red seas, Egypt. According to the Schaefer model (1954), the value of MSY was estimated at 73.0*10³ tons for Mediterranean sea fisheries, and at 63.1*10³ tons for Red sea fisheries. These values of MSY were obtained at fishing effort (f_max) of 3.5*10³ & 1.6*10³ standard boats in Mediterranean & Red seas respectively. The results indicated that the optimum exploitation in Egyptian marine fisheries required an urgent reduction in fishing effort. These results confirmed the overexploitation situation of the marine fish stocks in Egypt.